If you want finer-grained distribution, I think a better structure is:
```
switch(rng(1, 10)) {
   case1: case 2:
      //Some Ant food.
      break;
   case 3: case 4:
      // Lots of Ant food.
      break;
   case 5:
      // Hermit cave.
      break;
   default:
      // 50% chance of bupkis.
      break;
}
```
Especially since the hermit cave isn't actually 1/10, stacking the checks skews the probability such that "none" is a good bit less than 50%, but it's not intuitive that that's the case.